Investigators in the Central Asian nation of Uzbekistan are trying to determine the exact cause of Tuesday night's crash of an Uzbek airliner carrying 32 passengers and five crew members. No survivors were found among the wreckage at Tashkent's airport, which was shrouded in fog at the time of the crash.

Uzbek investigators are examining the plane's black box flight recorder for clues as to why the Soviet-built passenger plane crashed on approach to Tashkent's airport late Tuesday.

The United Nation's top official in Uzbekistan is among the dead.

Investigators say at this point there is no evidence to suggest a terrorist attack, but that the possibility will be examined.

The United States recently warned its citizens in the Central Asian nation of an increased threat in Uzbekistan, which is a key U.S. ally in the global fight against terrorism.

The Uzbekistan Airways Yak-40 airliner, in use for nearly 30 years, was just 1,000 hours short of being taken out of service when the crash occurred.